An audio device such as a digital mixer generally includes a plurality of channels, such as input channels and output channels. Generally, each channel is constituted of a plurality of processing blocks. For example, for an input channel, the processing blocks are an attenuator (ATT), an equalizer (EQ), a gate (GATE), a compressor (COMP), and the like. Each processing block executes signal processing based on values of a plurality of parameters which are set thereto. The user can arbitrarily set the values of these parameters in each channel by operating respective controls on a control panel, or the like. Generally, a plurality of parameters defining operation of one processing block is controlled with a plurality of individual controls corresponding to the respective parameters.
Further, there is known technology for linking parameters to one common control and controlling the linked parameters in an interlocked manner using the one common control. For example, PTL1 below discloses a parameter setting device capable of changing values of a plurality of items of parameters in an interlocked manner according to a predetermined variation table by operating one knob, which is a common control (see paragraphs 0018, 0024 to 0028, and so on of PTL1).